Photoprinting device



Feb. 2, 1943. J. HORN 2,310,148

' PHOTOPRINTING DEVICE Filed March s, 1941 z shuts-sheet 1 E i Jos-f- Hoe/d Feb. 2, 1943. J. HORN 2,310,148

PHOTOPRINTING DEVICE Filed March e, 1941 2 sheets-sheet 2 xaxeeigaxaxax I JOSEF Hoe/V Patentedv Feb. 2, 1943 UNITED sTATEs i PATENT OFFICE rno'roramrmo DEVICE Josef l'orn, Wiesbaden-Biebrich, Germany; vested in the Alien Property Custodian Application March 6,1941, Serial No. 381,999

l In Germany February 26, 1940 6 Claims.

larly to its direction of motion all over the glass plate so that the copying material may be uniformly illuminated.

The present invention relates to a photoprinting device of the afore-described kind in which a mercury vapor high-pressure tube is used as a source of light. A considerable evolution of heat of the mercury vapor tube becomes inconvenient insofar as the glass plate serving/for placing the copying material thereon, is strongly heated; this may have a. detrimental action on the copying material which in most cases is very sensitive-to heat. By causing, as is known by photoprinting devices of other kinds, a current ofcooling air to pass between glass plate and mercury vapor tube, the glass plate, it is true, is effectively cooled. At the same time, however, a strong cooling of the mercury vapor tube takes place, this being very detrimental. As is kno the emission of light of said tube considerably decreases when it is cooled. The device in quesexception of the apertures of 'the two nozzles.

such a mode of arrangement any cooling of the luminescent tube is most safely avoided. A construction has been found to be'the most advantageous according to which two nozzles are formed at both sides vof the luminescent tube by the edges of the reilector and the edges of a casing surrounding the reector. Care is thus taken that the reilector, tool, is cooled by the current of air produced, whereby the heat produced within the glass plate is indirectly also reduced. According to the mode of construction in question of the device of the present invention a suction piping is introduced centrally into the chamber formed by the reilector andthe casing named above. The chamber is closed with the By an arrangement oi said kind the suction at tion is provided, according to the present invention, with a cooling apparatus of a special kind by which it is possible to avoid the afore-named drawbacks. r

According to the present invention nozzles are provided in a photoprinting device of the kind herein described. Said nozzles are connected with a suction pipe or a compressed air piping. They are situated near the glass plate along the two edges of the reflector which are parallel to the axis of the lamp. The apertures of the nozzles are directed towards the glass plate. vMoreover, it -is necessary that the nozzles situated at both sides of the reflector are arranged in about the same distance from the source of light. It is suitable to provide on each side of the reiiector a slot nozzle extending all over the length oi' the reflector. It is, however, also possible to subdivide each of the two long slot nozzles into a row of short nozzles. 'I'he nozzles 'are connected according to the invention with the system consisting of luminescent tube and reilector so that they move together with said system. The glass plate serving for placing the printing material thereon may be cooled by means of the cooling device herein described and the source oi' light is not affected by the cooling air.

lt may be advisable to mount the nozzles closely to the longitudinal edges of the reflector. By

both nozzles is uniformly strong. It is also possible to operate with compressed air, but this mode is less advisable. By applying suction air it is possible by a simplerway to lead into the atmosphere the cooling air after it has been heated. A suitable method of eliminating the cooling air is extremely advisable owing'to its high content of ozone. The new kind of cooling is, of course, also suitable if instead of the mercury vapor high pressure tube there is used another source oi' light evolving much heat but being sensitive to cooling.

According to the invention the suction pipe or pressure pipe of the cooling device connected with the source of light is preferably introduced into l an aperture of a band exte ding along the path of motion of the suction iping. By said band the open part of a canal is closed; said canal also extends along the path of motion of the suction pipe or pressure pipe and in its interior is lin connection with a pump, a ventilator or the like. The aforesaid band is displaceable above the open part of the canal, while maintaining its packing effect. l

The device according to the present invention is diagrammatically illustrated, by way ci example, in the accompanying drawings.

Fig. 1 is a longitudinal section` on line l-I of Fig. 2,

Fig. 2 is a plan of the device, the copying the suction canal 2 L which a glass plate 2 has been inserted. Above said glass plate a lid 4 provided with a rubber Joint s is mounted. By means oi said lid it-is l possible to press the original andthe photographic printing paper to the glass plate. Below the glass plate a casing 5 is mounted which has the form of an elongated trough and is connected with rollers S sliding in. rails 1. The casing is moved toand fro with a defined velocity below the glass plate, and it is driven by an electromotor which is built together with a reduction gear 9. The chain wheel i0 is situated on the driving journal of the gear and causes by way of chain H and chain wheel i2 the shaft i8 to move. The latter is carried on the bearings id. 'I'he chain wheels 38 as well as the chain wheels is being on the same axis with the chain wheels t@ are driven by way oi the chains 'lo which are guided on the chain wheels i5 at the ends oi shaft i3. The two chains il? are driven with constant velocity by the chain wheels id. The axles of the chain wheels la and 38 are carried on the bearings i9. Chain Wheels 8l the axles of which are carried on the bearings iid also serve for guiding the chains besides chain wheels it. A haulage bolt revolving with the chain is mounted at each of the two chains. The two bolts 2t are engaged in driving arms 2i which are mounted to the casing 5 and are provided with a slot A wherein the bolts E@ may vertically move up and down. By the store-named connection the casing is taken along with the chains il and moves to and iro below the glass plate 2 when the chains are rotating. The casing is subdivided into three'divisions by two partitions 22. The reilector 2a is situated in the central part and is mounted at the partitions 22 so that two nozzles 2t are formed by its upper edges and the casing b. The space between the reilector 23 and the casing 5 is connected with the suction piping 25. The vmercury vapor high-pressure tube 2S -is arranged in the focus of the reflector 23 and is mounted in the partitions 22 so that the two heads which are particularly sensitive tothe action of cold are situated in the outer parts of the casing d. The edgesof the reflector 23 arecurved in such a manner that the central portion of the nozzles 2d formed by said edges oi the reiiector and those of the casing 5 is narrower than the two outer portions. By the construction as herein described the cooling air is caused to flow uniformly all over the length oi the nozzles and care is thus taken that the entire copying surestaras below the glass plate. Since the suction pipe 2b is joined to the branch :it which is fastened at the band, the band Sti also moves to and iro over the canal 29. By this method of operating the ventilator 2s in motion is permanently in connection with the inner space formed by reflector 23 and casing 5 and air is permanently sucked in by the nozzles 25. The air sucked up by ventilator 28 by way of tube iid is removed by the pressure piping 35 and must as a rule be entirely led into the atmosphere owing to its ozone content.

I claim:

1. in a device of the kind described a glass plate serving for placing the copying material face is uniformly cooled. Below the path oi' motion of the suction pipe 25 there is mounted a canal 29. of rectangular section which extends along the entire path of motion of the suction pipe. The canal is open towards the top part. The aperture is closed in an air-tight manner by an endless band 30 which is passed over the rollers Si. Metal rods 32 may serve for stienlng the band to which they are fastened and extend all over vthe breadth of the band. The bot-a tom part of the suction pipe 25 is joined to a branch 33 which is fastenedto the endless band '30; there is thus attained a connection between "the suction pipe 25 and the interior of the canal nozzle 24 formed by the reflector 23 and the cas- 75 thereon, rails extending along said glass plate, a casing between said glass plate and said rails extending perpendicularly to 'the direction of said rails over said glass plate, having the form of an elongated trough directed with its concave side towards said glass plate and being provided with rollers guided by said rails, a reflector arranged in said casing and being so constructed that two slot nozzles extending over said glass plate are formed by means of the longitudinal edges of said casing and the edges of said reflector, a mercury vapor high-pressure tube arranged in the focus of said reilector, a driving device serving for moving the system consisting of said casing, said reflector and said tube to and fro along said glass plate, a pipe fitting centrally into the space between said reflector and said casing, a canal the interior of which is connected vwith a suction device arranged beneath said casing and the vsaid rails, extending along the path of motion of said casing and being open on the side directed towards said casing and a hand above the openside oi said canal forming a displaceable closure y of said canal, the said pipe fitting into an aperture of said band. f

2. In a photoprinting apparatus, a glass plate serving for placing the copying material thereon,

va luminescent lamp in the form oi a tube evolving much heat but being sensitive to cooling near said glass plate and extending along said glass plate, a reflector surrounding said lamp so as to concentrate the light oi the lamp on said glass plate, a casing v.surrounding said redactor in such a manner that the edges of the reector and the edges of said casing form nozzles near said glass plate, which nozzles are directed towards said glass plate, the said lamp, reflector and casing being rigidly connected with one another, an airing device joined with the space between said reiiector and said casing and' means for moving the said system consisting of said lamp, reector and casing to and fro along said glass plate pere pendicularly to the axis of said lamp.

3. In a photoprinting apparatus as claimed in claim 2, a mercury vapor high-pressure tube as luminescent lamp.

4. In a photoprinting apparatus, a glass plate serving for placing the copying material thereon, a mercury vapor high-pressure tube near said glass plate and extending along said glass plate, a reiiector surrounding said tube so as to concentrate the light of the tube on said glass plate.

said tube, reflector and casing to and fro along 10 reector and said casing.

said glass plate perpendicularly to the axis of said tube.

5. In an apparatus as claimed in claim 4, -rails extending along the path of. motion of said system consisting of said tube, said reflector, and

rollers are guided by said rails.

6. A device as claimed in claim 4, wherein said pipe fits centrally into said space between said said casing, rollers fastened to said casing, which JOSEF HORN. 

